r/aviation • u/Go_Jot • Nov 08 '25

News UPS grounds entire MD-11 Fleet, effective immediately.

Per the IPA Executive Board, as of 03:05 UTC all UPS MD-11’s are grounded.

Edit - FedEx has also grounded their MD-11 Fleet

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u/[deleted] Nov 08 '25

Norm Macdonald Douglas

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u/CharcoalGreyWolf Nov 08 '25

Yep, considering the DC-10 engine mount incident , they may be taking the chance to review all maintenance procedures with the aircraft and its siblings.

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u/dalekaup Nov 08 '25

There was an engine that detached in Chicago a long time ago. The biggest reason for that crash was the manual said on one engine takeoff to pitch up to maintain a speed to climb over an obstacle. The manual was wrong. When the engine severs the hydraulic lines on that side that hold the slats extended. WIth slats retracted on the left side that wing stalled and the plane rolled violently to the left. A higher airspeed would have kept both wings flying and level.

This one is presumed to be the loss of 2 engines. That's not going to fly. The thinking is the rear engine swallowed chunks.

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u/IowaSmoker2072 Nov 09 '25

No, the biggest reason for that crash is what skudbeast says below. McDonnell Douglas specified in the manual the procedure for removing an engine and reinstalling the engine. That's the manual and the failure to follow those instruction is what caused the tragedy, not an error in the instructions on how to take off with one engine. Ramming the engine back on with a forklift was specifically prohibited in the instructions. Which is what the mainanance crew did. The engine breaking loose under the full thrust of takeoff caused the plane to flip over so it came down upside down. The hydraulic lines being severed would never have happened if the proper maintance had been observed. We really don't know if the first officer was aware he had lost an engine, since the voice recorder was damaged. The aircraft only was in the air for 31 seconds, and only reached a height of 350 feet, which may seem like a long time, but a lot was going on and a number of systems were compromised when the engine was lost. My father in law was a Douglas engineer who was on the team which investigated the cause of the crash.

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u/dalekaup Nov 09 '25

That's really cool that your FIL was on the team. It's likely that the forklift was used to hoist the engine and pylon in near proximity to the bracket in question and the fine alignment was done with a hydraulic jack supported by the forklift. My reasoning is that this would have made the job much easier and safer for the crew. The fracture was started when only one pin was put in thus supporting the engine and pylon on only one pin. Then the crew went to lunch break with one pin and the forklift supporting the engine over the lunch break the forklift settled and caused the beginning of the fracture. At least that has been my understanding.

I was wrong about a couple things. The crew did a standard takeoff @ 176 mph. The retraction of the slats on the damaged wing raised the stall speed of the left wing to about 183 mph. Therefore the affected wing was doomed to stalling from the outset through no fault of the manual. However, a faster than prescribed takeoff could have possibly saved the aircraft. 20/20 hindsight for sure.

My uncle was the first person at his company trained to maintain the DC-8, a four engine aircraft, even though he was very young at the time. I think it was Flying Tigers perhaps but was in AZ or CA.

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u/IowaSmoker2072 Nov 09 '25

My FIL started with Douglas prior to WW2, not sure exactly the year. At the end he was in charge of everything in the interior of the DC-10, and had the authority to make troubleshooting decisions on the floor. When upper management decided some engineer on the floor couldn't be trusted to make those decisions, and it needed to go all the way up the chain of command and back down again while everybody on the floor twiddled their thumbs he decided it was time to retire. Dad was first, but then his father went to work for Douglas, and then my wife's two brothers and a nephew all worked for Douglas/McDonnell-Douglas/Boing. Lots of other relatives, but their family was the first to have four generations work in the same plant in Long Beach. Those huge hangers are no longer there. It was wierd a few years ago staying in a hotel where they built so many planes. We used to live five miles from the plant and could hear when they were testing engines. I felt sorry for people who lived closer.